In an environment of long-time running, for reasons such as capacity expansion and equipment replacement, disks having different performance and capacities exist in a distributed storage system including Ethernet. The performance and the capacities of the disks affect performance and a capacity of the entire system. It is of worth to research on how to fully bring the performance and the capacities of the disks into play to ensure maximization of the performance and the capacity of the distributed storage system.
In the prior art, a distributed storage system generally allocates stored data according to capacity proportions of disks. More stored data is allocated to a disk with a larger capacity. For example, for a disk with a capacity of 4 terabytes (TB) and a disk with a capacity of 2 TB in a system, more stored data is allocated to the disk of 4 TB than that allocated to the disk of 2 TB according to a capacity proportion.
However, performance of a larger-capacity disk may be the same as performance of a smaller-capacity disk. For example, input/output operations per second (IOPS) of a larger-capacity disk may be the same as IOPS of a smaller-capacity disk. Therefore, if the foregoing stored data allocation method according to capacity proportions is used, it is likely that system storage performance is severely affected because storage space of a smaller-capacity disk has been used up, but a large amount of storage space of a larger-capacity disk is still available, and therefore storage performance of each disk cannot be fully brought into play, and storage capacities cannot be fully used.